The invention is based on an rpm regulating device for an internal combustion engine having a throttle device in the air intake tube and an associated controllable bypass as an air diversion channel. During idling, the cross section of this bypass channel can be varied in order to regulate rpm. In this known rpm regulating device, the bypass cross sectional opening has an average opening cross section outside the area of idling rpm regulation, from which point on the regulation is initiated.
It has been found that this known regulating device is not capable of providing satisfactory results in all cases, particularly in terms of favorable exhaust gas figures and additionally in providing sufficient protection against engine stalling.